Can we use automated data to assess quality of hypertension care?

OBJECTIVE: To determine whether extractable blood pressure (BP) information available in a computerized patient record system (CPRS) could be used to assess quality of hypertension care independently of clinicians' notes. STUDY
DESIGN: Retrospective cohort study of a random sample of hypertensive patients from 10 Department of Veterans Affairs (VA) sites across the country.
METHODS: We abstracted BPs from electronic clinicians' notes for all medical visits of 981 hypertensive patients in 1999. We compared these with BP measurements available in a separate vitals signs file in the CPRS. We also evaluated whether assessments of performance varied by source by using patients' last documented BP reading.
RESULTS: When the vital signs file and notes were combined, a BP measurement was taken for 71% of 6097 medical visits; 60% had a BP measurement only in the vital signs file. Combining sources, 43% of patients had a BP reading of less than 140/90 mm Hg; by site this varied (34%-51%). Vital signs file data alone yielded similar findings; site rankings by rates of BP control changed minimally.
CONCLUSIONS: Current performance review programs collect clinical data from both clinicians' notes and automated sources as available. However, we found that notes contribute little information with respect to BP values beyond automated data alone. The VA's vital signs file is a prototypical automated data system that could make assessment of hypertension care more efficient in many settings.